The percent change in multifactor productivity if Fok can reduce the energy bill by $1000 per day without cutting production or changing any other inputs = nothing% (enter your response as a percentage rounded to two decimal places).

When cell phones were first entering the market, they were relatively large and reception was undependable. all cell phones were essentially the same. but as the technology developed, many competitors entered, introducing features unique to their phones. today, cell phones are only a small fraction of the size and weight of their predecessors. consumers can buy cell phones with color screens, cameras, internet access, daily planners, or voice activation (and any combination of these features). the history of the cell phone demonstrates what marketing trend?